What is an antibody test?
What is an antibody test, an antibody test is a test that shows whether a person has ever been infected with the COVID-19 virus.
Antibodies are proteins that exist in the human body and help the immune system understand, identify and eliminate threats from outside.
Antibody testing is performed in laboratories accredited by the Ministry of Health. In the short term, the person who has an antibody test can see whether they have previously been immunized against the covid-19 virus.
People who test positive for antibodies should also have a PCR test to see whether they still carry the virus and, most importantly, whether they are still contagious.
Who should have an antibody test?
Who should take the antibody test, people who want to find out whether they have had the COVID-19 virus before can take the antibody test.
There are two types of antibody test;
1.Early Response: (Immunoglobulin M)
2.Late Response: (Immunoglobulin G)
The purposes of antibody testing;
- To monitor the course of any infection in the body
- To be able to assess whether the body has been exposed to a potentially infectious antigen and whether this has occurred
- See and diagnose problems caused by autoimmune disorders, HIV, liver diseases and symptoms, hepatitis, thyroid, syphilis, allergies, lupus, etc.
- Investigating and assessing the reasons why the bodies of people who may have a transplant or transfusion reaction reject it
Antibody testing is performed for the reasons mentioned.
What is the link between antibody testing and COVID-19?
In the application of antibody tests for COVID-19, several different analysis methods and different antibody types are analyzed.
These types of analysis are IgG, IgM and IgA immunoglobulins.
The antibody test provides information about a recent infection. It is not yet clear how long this period lasts. In the short term, people who can show antibodies in their body between 10 or 20 days may have had Covid-19 and have become immune to it, but in this case, the second most important step must be taken. That step is that people with a positive antibody test must have a PCR test. Because in the current situation, the antibody indicates that the person has encountered the covid-19 virus, it does not show whether the person is still a carrier or not, so the person must also have a PCR test.
How is the antibody test performed?
The antibody test is of two types as mentioned above,
1. Early Response: (Immunoglobulin M)
2. Late Response: (Immunoglobulin G)
Immunoglobulin M and Immunoglobulin G are both performed in early response. Antibody tests applied in Turkey are currently of two types.
The first of these two types is known as the rapid test, which we call the card test, commonly known as the card. The test we call card test can show us the result within two hours. Blood is taken from the person for this test and either a line or no line is formed as a result of the chemicals in this blood card test panel. The absence of a line means that the test is negative.
If there is any line in the Immunoglobulin M section, it means that the person has Immunoglobulin M type antibody. This means that the person has an early response.
If there is a line in the Immunoglobulin G band; it means that the person has and has Immunoglobulin G type antibody. This means that the person has a late response.
The positive result of the test we use to detect IgA and IgM antibodies against Covid-19 infection tells us that the person has recently encountered the covid-19 virus.
This may also be the opposite of the current situation. Because a certain and sufficient time has not yet passed for infected patients to respond to the virus, that is, to develop antibodies, it can also be negative.